Arctic streams are strongly affected by two key factors that may be responsible for landscape patterns in community structure: freezing and physical disturbance in the form of bed movement. We used the habitat template approach to investigate the effects of freezing and substratum movement on food webs of twenty headwater streams on the North Slope of Alaska. Substratum movement was measured indirectly using estimates of tractive forces and particle size distribution and directly using particles marked in situ. Of the 8 streams fed primarily by groundwater, 4 froze during winter and substratum movement ranged from 0-14%. Eight of 12 streams fed by surface runoff froze and substratum movement ranged from 4-97%. Preliminary data from 10 streams shows that structural variables of invertebrate taxonomic richness (11-60 taxa) and mean food chain length (1-3) vary little with respect to freezing and bed movement among stream types. However, functional variables such as mean biomass (0.01-3820 mg m^-2) and predator:prey ratio (0-0.3) strongly differ as a function of both freezing and bed movement. Therefore, contrasts in freezing and bed movement patterns among these twenty streams are expected to have minor effects on community structure, but substantial effects on function.